Distributed Adaptive Consensus Protocols for Linear Multi-agent Systems with Directed Graphs in The Presence of External Disturbances

This paper revisits the distributed adaptive consensus protocol in [1] when the agents are subject to external disturbances. To deal with the parameter drift phenomenon associated with the adaptive protocol in [1], we propose a novel distributed adaptive protocol by using the sigma modification technique. It is shown that this novel adaptive protocol can guarantee the ultimate boundedness of both the consensus error and the adaptive coupling weights for linear multi-agent systems whose communication graph contains a directed spanning tree with the leader as the root node, and thereby is robust in the presence of external disturbances.